New data from a public health registry that tracks the health effects of 9/11 suggest that as many as 70,000 people may have developed post-traumatic stress disorder¹ as a result of the terrorist attacks.

The estimate, released Wednesday by New York City's Department of Health, is based on an analysis of the health of 71,437 people who enrolled² in the World Trade Center Health Registry. They agreed to be tracked for up to 20 years after the Sept. 11, 2001, attacks, and the study was based on answers they volunteered about their health two and three years after the attack.

Of the estimated 400,000 people believed to have been heavily exposed to pollution from the disaster, data suggests that 35,000 to 70,000 people developed PTSD and 3,800 to 12,600 may have developed asthma³, city health officials said.

They include rescue and recovery workers, lower Manhattan residents, area workers, commuters and passers-by.

Overall, half of the respondents said they had been in the dust cloud from the collapsing⁴ towers; 70 percent witnessed a traumatic sight, such as a plane hitting the tower or falling bodies; and 13 percent sustained an injury that day.

"The consensus⁵ among physicians is that when it comes to physical health, the vast majority of people felt symptoms in the first year," said Lorna Thorpe, the deputy commissioner⁶ for epidemiology at the New York City Health Department. "A small proportion of people, however, developed symptoms years later. And in some cases, it's hard to tell whether they're World Trade Center-related or a result of allergies⁷ or existing conditions."

The post-traumatic stress disorder rate was highest among injured, low-income and Hispanic study volunteers. In general, minorities and low-income respondents experienced higher rates of mental and physical problems, as did women.

The study was conducted by the city health department and the federal Centers for Disease Control's Agency for Toxic⁸ Substances and Disease Registry. It was released in the Journal of Urban Health.

 据一个公共健康登记机构发布的最新数据显示，当年的9•11恐怖袭击导致7万人患上了“创伤后应激障碍综合症”（PTSD）。这家机构一直在跟踪调查9•11事件给民众健康造成的影响。

纽约市卫生署于本周三发布的这项评估，主要根据对“世贸中心健康登记机构”71437名成员的健康状况进行分析后得出。这些成员同意自2001年恐怖袭击事件后接受该机构长达20年的健康跟踪调查。而这项研究的依据就是他们在事后两三年提供的关于自身健康的报告。

9•11造成的污染让约40万人的健康受到严重伤害。据市卫生署的有关官员介绍，统计数据显示，有3.5万至7万人患上了PTSD心理后遗症，另有0.38万到1.26万人可能得了哮喘。

这其中包括参与事后救援和重建的人员、曼哈顿下城区居民、区域工人、上班族和过路人。

总体来看，有一半的受访者称当时他们被笼罩在大楼倒塌产生的巨大烟尘中，70%的人亲眼目睹了飞机撞上大厦和尸体横飞的恐怖场景；还有13%的人受了伤。

纽约市卫生署流行病科副主任罗娜•索普说：“医学专家普遍认为，在生理方面，大多数人在事后的第一年就感觉到了症状；也有一小部分人是在几年后才呈现出病状。有时则很难判断他们的症状究竟是与世贸事件有关，还是由过敏或已有病症引起的。”

心理障碍综合症发病率最高的人群是受伤者、低收入人群和西班牙籍研究志愿者。总体来看，少数族群、低收入者和妇女在9•11后患心理和生理疾病的比率普遍较高。

该研究由纽约市卫生署和联邦疾病防控中心有毒物质与疾病登记处联合开展，研究结果在《城市健康杂志》上发表。